Currently, display technologies have been widely applied, and display devices used for displaying images are many and varied, and can display various images. With the rapid development of flat-panel display technologies, the demand for the image quality of the display devices is increasing.
Image residual is an important factor to evaluate the image quality, and has aroused wide attention for a long time. For a display device, for example, a liquid crystal display panel, in the case that one image being displayed for a long time, because of the long time effect of the electric field, an afterimage may occur when switching to other images. The main reasons for the occurrence of the image residual is as follows: charged ions will be introduced in the display device during manufacturing processes of the display device and material, and in the case that one image being displayed for a long time, the above charged ions will be separated under the external electric field, and therefore an internal electric field is formed. The internal electric field formed by the above charged ions makes the display device maintain the last image when switching to other images and therefore the afterimage occurs.
Peripheral image residual is one type of image residual that often occurs in the display device. The main reasons for the occurrence of the peripheral image residual include: contamination of the liquid crystal molecules inside the LCD panel is caused by the sealant disposed at the peripheral area of the LCD panel, charged ions caused by the contamination are distributed at the peripheral area of the LCD panel, an internal electric field is formed by the charged ions during the display device displaying an image, the internal electric field formed by the above charged ions makes the display device maintain the last image when switching to other images, and therefore the peripheral image residual occurs.
Therefore, the peripheral image residual issue of the display device needs to be solved.